Pneumatic door-check



(No Model.)

J. W. WETMORE. PNEUMATIC DOOR CHECK.

No. 502,841. Y Patented Aug. 8, 1893.

Wilnessew.

UNITED STATES PATENT Orricn.

JEROME W. WVETMORE, OF ERIE, PENNSYLVANIA, ASSIGN OR TO THE VAN WAGONER& WVILLIAMS COMPANY, OF JERSEY CITY, NEIV JERSEY.

PN EU MATlC D'fOOR-CHECK.

SPECIFICATION forming part of Letters Iatent No. 502,841, dated August8, 1893. Application filed June 25, 1883:. Serial No- 99,134. (Nomodel.)

T0 at whom it may concern.-

Be it known that I, JEROME W. WETMORE,

citizen of the United States, residing at-Eri,

in the county of Erie'and State of Pennsylvania, have invented a new anduseful Improvement 1n Pneumatic Door-Checks, of WhlCll the following isaspecification.

Door checks embodying my invention, be-

long to that general variety, which are used upon doors, whichareprovided with springs for closing them, Whether said springs beorganlzed as parts of hinges, or separately applied tothe door andframe.

One object of my invention, is the produc- Mom of a simple, compact, andeffective pneumatic door-check, having an extensive rangeof rapidmovement as between the piston and 1ts cylinder, and to accomplish theseends, I have for the first time so organized an air cylinder, that itoscillates on a central axis during the swingingmovements of a door whencontrolled by the door'check; In other words, my door check includes incombina-v tion an air cylinder, a bracket by which said cylinder issupported ina horizontal position for service, and to which saidcylinder iscen trally pivoted to enable it to oscillate as on a verticalcentral axis during the swinging movements of a door, a piston slidingin the cylinder, and a piston rod provided with a pivoted arm at itsouter end.

Another object of my invention is to provide for a prompt release ofcompressed air within the cylinder 3' ustprior to the complete closureof a door, and this I accomplish for the first time, as I believe, bythe combination with the air chamber, of a piston and an automaticallyoperated valve which is opened by the piston just prior to thetermination of its air compressing movement, and I have still furtherprovided for variably adjusting the valve operating devices, so that therelease of air pressure can be graduated to exact requirements.

hereunto annexed. I Referrmg to the drawings, Figure-1; illustrates adoor and its frame, with one of my oscillating cylinder doorcl ecks, asapplied to operate at the inner side of the door, the

latter being shown in an opened position. Fig. 2, illustrates the sameparts, with the top of the door frame removed, for showing the doorcheck in top or plan view; and in dotted lines, the positions of thedoor and the check are indicated, as when the 'door has been nearlyclosed. Fig. 3, illustrates the air cylinder in vertical longitudinalsection, and containing a piston, its piston rod, and pivoted arm, saidpiston being of ordinary construction, Fig. 4, illustrates a door-frameand a closed door, provided with a well known form" of door spring, anda door check having a non oscillating cylinder containing my automaticvalve. Fig. 5, is a topor plan view of the door, its frame, and the doorcheck of Fig. 4.. Fig. 6, is an enlarged view of the door "check of Fig.4E, detached; Fig. 7, in vertical longitudinal section, illustrates aportion of the air cylinder, its piston, its automatic valve, and itsadjusting device.

, That portion of my invention which includes the oscillating aircylinder, is illustrated only in Figs. 1, 2, and 3,'-in which my doorcheck is shown as applied to a door A, and its frame B. Y

The air cylinder 0, is for the first time pivoted so'as to oscillate ina horizontal plane, as on a vertical central axis, this latter beingafforded by means of trunnion pivots o, c, and a bracket c and in thiscase a socket 0, serves as a bearing for one of the pivots. The pistonG, within the cylinder is provided with a rod D, which occupies a largecentral opening in the front end C of the cylinder, and is pivoted atits outer end to the arm E, by means of which, proper connection is-madewith the door.

As clearly indicated in Fig. 2, the outward swinging movement of thedoor, to the extent of ninety degrees or a little more, causes thepiston to move the entire length of the interior of the cylinder. Theinward movement of the piston is very rapid duringthe earlyclosingmovement of the door, butduring the terminal closing movement, the;piston moves very slowly against the air cushion promptly developed atthe outset, by the action of a door spring of any kind, as for instance,the

ICO

well known torsional spring S, shown in Fig. 4. The piston G of Fig. 3,with its packing g, valve II, spring I, central opening I, and bailstrap F, are all substantially as heretofore.

For promptly releasing the compressed air, I have devised an automaticvalve, which when applied in its simplest form, affords no externalevidence of its presence, and hence it is not shown in all of thefigures.

In Fig. 7, I illustrate said automatic valve, as employed in connectionwith any form of door check air cylinder, whether it be arranged tooscillate in accordance with one portion of my invention, or pivoted asheretofore, either at its extreme rear end, or at its extreme front end.

The piston G, has its rod D, coupled thereto by a bail strap F, in amanner well known, and any suitable packing g, is employed for securingclose contact with theinterior of the cylinder 0. There is a port oropeningin the piston, covered by a spindle valve II, which is normallyheld to its seat by a light spring I On the front side of the piston, alever L, is pivoted on asuitable projecting stud. One end of said lever,engages with the valve H, and its opposite end is bent or curved so asto pro ect far beyond the end of the piston, so that as the piston nearthe end of its stroke, causes the bent end of the lever to strikeagainst the inner or closed end of the cvlinder, the valve will belifted from its seat, and the compressed air permitted to freely escapethrough the piston into the front portion of the cylinder, and out intothe open air through the large opening in the.

head 0', which is only partially occupied by the piston rod. The springof the valve 11', is so light thatwhen the piston is moving outward, aircan freely pass through the port to the closed end of the cylinder. Itwill be seen that in ,order to render this automatic valve adjustable inits releasing action, the abutting point of the lever must be variable,

and I provide for this by the use of an ad justing thumb screw m,entering through the end of the cylinder to afford convenience inmanipulation, and the inner end of said screw, serves as the variableabutment with which said lever engages. It will be understood that thisautomatically operated releasing valve is applicable to air cylindershinged as heretofore, as for instance, as illustrated in Figs. 4. 5, and6, wherein the cylinder is mounted upon an open hinge bracket K, .I,having a hinge pin Z, and nails or screws j for attaching the whole inposition for service.

Having thus described my invention, I claim as new and desire to secureby Letters Patent-- 1. In a pneumatic door check, the combinationsubstantially as hereinbefore described, of an air cylinder, a bracketadapted to be applied to a door frame below its top and by which saidcylinder is supported in a horizontal position for service, and on whichsaid cylinder is centrally pivoted and capable of oscillating as on avertical central axis during the movements of a door, a piston, and itsrod provided with a pivoted arm at its outer end.

2. In a pneumatic door check, the combination with the aircylinder andits piston, of an automatically operated valve for releasing compressedair, just prior to the terminal air compressing movement of the piston.

3. In a pneumatic door check, the combination with the air cylinder andits piston, of an adjustable automatically operated valve for releasingthe air pressure, substantially as described.

4. In a pneumatic door check, the combination of the air cylinder, thepiston,a normally closed valve for controlling compressed air, and alever actuated by the piston for opening said valve, substantially asdescribed.

5. In a pneumatic door check, the combination substantially asdescribed,of the air cylinder, the piston, the normally closed valvethereon, the lever on said piston attached to said valve, and anadjusting screw serving as a variable abutment for contact by said leverduring the terminal air compressing movement of the piston, and causingsaid valve to open for releasing the compressed air.

JEROME W. IVETMORE.

